NYU’s Furman Center has posted a short Research Brief, Compact Units: Demand and Challenges. The brief notes that there is no formal definition of a compact or micro unit of housing, but
the term is typically used to refer to units that contain their own bathroom and a kitchen or kitchenette, but are significantly smaller than the standard studio apartment in a given city. Accessory dwelling units (ADUs) are self-contained units located on the property of a single-family home. Sometimes ADUs are separate structures, like a cottage on the same lot as a primary dwelling; sometimes they are attached to the primary structure, located in a basement, in an extension, or over a garage.
Proponents of compact units argue that they allow seniors to live independently, respond to changing household sizes and demographics, reduce sprawl through urban infill, mitigate the environmental effects of larger developments by reducing energy consumption, free up larger units for families, and help cities provide housing affordable to a wider range of households. (2)
The brief is a very useful overview of the debate concerning compact units but my own take is that they represent a mere molehill of possibility when it comes to affordable housing. No new construction in cities, unless heavily subsidized, is geared toward low-income households and probably only a small portion of such new construction is geared to moderate-income households. The economics of new construction just don’t allow it.
This is not to say that New York City shouldn’t change its larger-than-average minimum unit size regulations (400 square feet) so that they are in line with those of other cities (220 square feet). These small units could work well for all sorts of one-person households, which, by the way, make up more than half of all households in NYC. They just wouldn’t be low-income households. But, by expanding the total number of units available, they can put at least some downward pressure on rents.
My bottom line: compact units are good, but they will not provide the mountain of affordable housing that some claim they can.